Many engines, during the start up period, emit an over abundance of white smoke. White smoke is normally caused by incomplete combustion within the combustion chambers of the engine. For example, especially during start up, the cylinder or liner, the piston, the head and the other components in contact with the combustion chamber are cold. The cool configuration of the components extinguish the flame before burning is complete. As the piston moves from the intake stroke through the compression stroke, the temperature in the combustion chamber and the components in contact with the combustion chamber become warmer. At or near the top of the compression stroke, fuel is injected into the combustion chamber as small droplets of fuel and a portion of the mixture is rapidly burned. The remainder of the unburned small droplets of fuel is exhausted during the exhaust stroke as white smoke. The combination of the cool components and the incomplete cold combustion causes an excessive amount of white smoke to be exhausted from the combustion chamber and engine. As continued combustion takes place, the components are heated, the combustion becomes more complete increasing efficiency and white smoke is reduced. To overcome the start up problem, many engines are equipped with block coolant heaters. These heaters are electrically operated, draw a high current and require shore power to heat the electrical coils therein.
In some applications of high performance engines due to the high coolant efficiency, the temperature at idling condition within the combustion chamber components become cool enough to cause white smoke to occur. One example of white smoke at idling condition has been found to occur during marine pleasure craft trolling conditions. Attempts have been made to eliminate the white smoke by increasing the temperature of the coolant and eliminating the cool conditions in the combustion chamber. Such attempts have shown that the reaction time or responsiveness of such components used to control the temperatures is too slow and results in sporadic uncontrollable white smoke. The coolant temperature control systems are found to function properly under steady state condition but fail to compensate for rapidly changing conditions.